chemistry section 6.3-6.4 calorimetry and heat and change of state

ΔT=T_f - T_i

formula to measure temperature change

extensive property that describes how an object’s temperature changes with heat

heat capacity(C)

C=Q/ΔT

formula for heat capacity

intensive property that is the ratio of heat capacity to mass

specific heat ( c )

c=C/m=Q/mΔT

formula to find specific heat

heat required to cause a unit rise in the temp of a unit mass (1 g)of the substance

specific heat ( c )

formula to determine the energy transferred as heat, if the ΔT, c,and m are known

Q=cmΔT

device used for measuring heat

calorimeter

calorimeter open to the atmosphere, allowing ΔH to be obtained

constant-pressure calorimeter

calorimeter where a combustion reaction occurs in a pressure vessel at constant volume, allowing ΔE to be measured

bomb calorimeter

-(cmΔT)_sample=(cmΔT)_H2O

equation to find specific heat of an element in a calorimeter

graph that shows temperature as a function of energy added as heat

heating curve graph

energy per unit mass required to melt a substance at its melting point

enthalpy of fusion/heat of fusion

energy required to vaporize a substance at its normal boiling point

enthalpy of vaporization / heat of vaporization

what 2 groups have the same value but opposite signs ?

enthalpy of fusion and crystallization and enthalpy of vaporization and condensation.

heat that is used for a phase change or causes a phase change

latent heat

if the temperature is constant what does the rate of condensation depend on?

partial pressure of water vapor

state in which two opposite processes are continuously occuring at equal rates so they offset each other

dynamic equillibrium

partial pressure at which the liquid and vapor phases are in equillibrium

vapor pressure

temp at which the liquid’s vapor pressure equals the total pressure of all gases present

boiling point

what does the vapor pressure of a substance depend on?

forces that hold the atoms, molecules, or ions together.

process where a solid below the melting point can directly change into vapor, aka solid directly into a gas

sublimation

what is the process called when a vapor below the melting point will directly form the solid ? aka gas directly into a solid

deposition

partial pressure at which sublimation and deposition occur at the same rate and the solid and vapor phases are in equilibrium

vapor pressure of a solid

demonstrates the relationships between the different states of mate, showing the phase or state of a substance at different P or T

phase diagram

liquid to gas

evaporation

change of substance from a gas into a liquid

condensation

a substance’s melting point and boiling point at any pressure can be found by doing what on a phase diagram?

drawing a horizontal line at that pressure

how to find the state changes that will be caused by changes in pressure and temperature on the phase diagram?

drawing a line between the corresponding points

point where all three phases exist in equillibrium, without a net change of one phase into another.

triple point

point where the distinction between liquid and gas dissappears

critical point

fluid with properties intermediate between those of liquid or gas

supercritical fluid